I was wondering if anyone has any ways to check whether the ball valve on the pipeline is fully open?
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In some piping systems, although the fluid can be transported normally, the ball valve is not actually fully open. I wonder if anyone on the forum knows how to check whether a ball valve is fully open without causing any leaks?
Based on the position of the ball valve stem, it is fully closed perpendicular to the pipeline direction, and fully open in the same direction as the pipeline
Here’s the situation: Our company specializes in using balls to clean oil and gas pipelines. We have encountered ball valves on 12\" pipeline systems where, from the outside, the pointer indicated 90 degrees, suggesting that the valve was fully open; in reality, however, it wasn’t fully open. This condition affects the passage of pigs and internal detectors. But it’s not possible to stop the pipeline flow and take down each valve just to check it. So I would like to ask everyone if there are any good ways to determine whether the actual opening degree of the ball valve matches the external indication, without causing any losses.
It’s a ball valve with worm gear transmission, right? With such a valve, if the driving mechanism isn’t properly installed, it’s not accurate enough to judge merely by the pointer; however, such accuracy is generally not required. Its valve stem seems to be cylindrical; it’s impossible to tell from the outside, and I think the only way is to take it apart to check. The worm gear box can be disassembled to check whether it is in a horizontal position inside, but this does not necessarily mean that it is fully open or fully closed……
It’s a ball valve with worm gear transmission, right? With such a valve, if the driving mechanism isn’t properly installed, it’s not accurate enough to judge merely by the pointer; however, such accuracy is generally not required. Its valve stem seems to be cylindrical; it’s impossible to tell from the outside, and I think the only way is to take it apart to check. The worm gear box can be disassembled to check whether it is in a horizontal position inside, but this does not necessarily mean that it is fully open or fully closed……
It is indeed as you said. For the flow in pipeline systems, a ball valve can be used to isolate the flow; once it is opened, the fluid can flow normally. But for companies that specialize in ball cleaning, pigging, and internal inspection, it’s different – the slightest mistake can prevent the pigs and inspection devices from passing through. The last time we encountered this issue, it was just as you said; in the end we had to disassemble the transmission mechanism to take a look. It seemed that the tightening of the limit screw of the worm was improper, and the clearance between the gear and the worm was abnormal, which caused the actual opening angle to differ from the indicated opening angle. If there’s no better way, it seems this will be the only option going forward.
A ball valve looks just like this; its external appearance can only be used as a reference for its opening degree. To fully open a gate valve, just turn it to the top.
If a flow meter is installed on the pipeline, the opening degree of the ball valve can be determined based on the flow rate
Continue to turn left to open the valve, all the way； In this way, it can be confirmed that the valve is in the fully open position ； :lol
Could a mark be made at the shaft exit of the valve core?~~ This would help to check whether it is fully open or fully closed~~